Autoimmunity or hypersensitivity.

A low level of Autoimmunity is beneficial, period. High autoimmunity means a person is allergic to himself or herself. The immune system begins to destroy the person it should protect. It is thought to cause arthritis, diabetes, and a host of other diseases.

When the immune system mistakenly attacks a normal part of the body, this is known as autoimmunity.

Autoimmunity that causes hypOthyroidism (low thyroid) is called Hashimoto's Thyroiditis. This condition can also cause hypERthyroidism as well. There are specific antibodies in patients with Hashimoto's.

Autoimmunity that causes hypERthyroidism is usually a condition known as Graves' Disease. There are specific antibodies in patients with Graves' Disease.

Autoimmunity

A positive ANA test does not necessarily mean the patient has an autoimmune disease. An ANA test is not specific for autoimmunity, but is a sign of inflammation that is often specific to autoimmunity. Specific antibodies are usually tested for to determine if a patient has an autoimmune disease.